Anderson Cooper took issue with a guest's defense of President Trump on his show Friday night.

Jeffrey Lord regularly appears as a pro-Trump commentator on CNN. On "Anderson Cooper 360," Cooper asked Lord whether he thought Trump should be doing things like telling the Russians that fired FBI Director James B. Comey is a "nut job" while under investigation by the FBI.

"You can't really defend it, in all fairness," Cooper said. "You can't defend what the president of the United States just said."

"I don't care what he says to the Russian prime – to the Russians," Lord replied. "I mean, he's the president of the United States. If he wants to say that, if Barack Obama wants to say whatever, if George Bush says 'I looked in his eyes and' – "

Cooper interrupted him: "If he took a dump on his desk, you would defend it."

He continued: "I don't know what he would do that you would not defend."

Minutes later, Cooper apologized for saying it. He followed it up with a tweet:

Cooper recently earned the Internet meme treatment for an onscreen eye roll last week in response to Kellyanne Conway skirting a question about Comey's firing.